Article of manufacture and method of making the same



April 13 1926. 1,580,417

' C. B. CUSHWA ARTICLE OF MANUFACTURE AND METHOD MAKING THE SAME Filed June 9- 1924 I z fiVENTOR I Patented Apr. 13, 1926.

UNITED STATES 1,580,417 PATENT OFFICE.

CHARLES B. CUSHWA, OF YOUNGSTOWN OHIO, ASSIGNOR TO THE COMMERCIAL SHEARING AND STAMPING COMPANY, OE YOUNGSTOWN, OHIO, A CORPORATION OF OHIO.

ARTICLE OF MANUFACTURE AND METHOD OF MAKING THE SAME.

Application filed June 19, 1924. Serial No. 720,967.

'ToaZZ whom it may concern:

Be it known that I, CHARLES B. CUsHwA, a citizen of the United States, residing at Youngstown, county of Mahon'ing, and State of' Ohio, have invented a new and useful Improvement in Articles of Manufacture and Methods of Making the Same, of which the following is a full, clear, and exact description. v

The present invention relates broadly to metallic articles and to a method of mak ing the same, and more particularly to steel sheets or plates which are both worked and machined in accordance with the use to which they are put.

The particular shape of the sheet or plate is immaterial and will depend upon the use to which it is to be put; Therefore, throughout the specification and claims, I have used the word {plate in its most generic sense as being de nitlve of flat or curved sheets or plates.

For purposes of illustration, the present invention will be described as applied to the manufacture of a tube plate or header for boilers, tanks and the like, it being apparent that this is merely one of the uses to which the'invention may be placed.

At the present time, it is customary to construct such tube plates either of cast-iron or steel. The cast iron has been more or less objectionable due to the fact that it p0s sesses but little flexibility, relatively little strength as compared to steel, and involves an expensive manufacturing operation. Where steel has been used, it has usually been open-hearth steel due to the properties of this steel enabling it to be easily worked. These same properties, however, prevent the steel from being effectively machined, as for example threaded, thereby making it necessary wherever pipe connections are to be made, to weld or otherwise secure a malleable bushing either into a suitable opening or onto one surface of the plate. During installation, it frequently happens that such bushings are broken either partly or entirely loose, thereby rendering such constructions also objectionable.

It is well recognized that steel, having peculiarly different properties, is produced by the Bessemer process and by the open-hearth process. Whether these processes are of the acid or the basic type the characteristics of the Bessemer steel are distinctly different from those of the open-hearth steel. During the Bessemer process, the percentage of car- 'bon and manganese may be accurately controlled, the phosphorus and sulphur being of slightly greater percentage in the finished steel than in the original pig iron owing to a loss in weight due to oxidation and eliminating of the silicon, carbon, manganese and a part of the iron. Where the Bessemer steel is to be used for the making of screw steel or the like, it is given a high sulphur content, usually by the addition of sulphur in the form of pyrite. This steel possesses properties enabling it to be easily machined, as for example threaded, without an difficulty. It is, however, exceedingly difiicult to work the metal as the working sets up strains tending to produce cracks.

The open-hearth steel, on the other hand, contains relatively little phosphorus and sulphur, thereby providing a steel which may be effectively worked, but which is incapable of being easily machined. Experience has-shown thatit is almost impossible to thread steel of this character. During the open-hearth process, the sulphur, silicon, manganese and phosphorus are all removed before the carbon.

From the foregoing, it is apparent that neither of the steels possesses properties enabling it to be effectively worked and machined. The amount of carbon can be accurately controlled in either process and where present in amounts less than. 1% imparts hardness, strength and ductility to the metal. Above this amount, the brittleness of the steel increases very rapidly. In the steel produced by either process, however, the desired amount of carbon may be maintained. The presence of manganese in quantities above .3% raises the tensile strength of the steel, while above 1%, it produces undue hardness and brittleness. The presence of the carbon and manganese. therefore, largely determines the characteristics of the steel produced by either process.

The presence of sulphur, where manganese is also present, forms a manganese sulphide which, when present in sufliciently large quantities, imparts to the steel a fibrous structure similar to that of wrought iron, thereby peculiarly adapting the steel to a threading or other machining operation. Likewise, phosphorus, although sometimes considered'as objectionable, is desirable in chined.

In the figure of the drawings, I have illustrated diagramn'latically a portion of a plate 2 shaped in accordance with one feature of the present invention. This plate is of 'open hearth steel permitting a neck or boss 3 to be easily pressed or punched outwardly from the main body of the plate. This boss is thereafter heated, preferably to a temperature above red heat, and a coating of sulphur, phosphorus, or both, or of either or both of these elements in combination with other'elements capable of imparting Bessemer or wrought iron characteristics to the steel is applied locally. In the illustrated example, this application is made to the in} terior of the neck. The coating combines chemically with the basic steel low in the elements of the coating and imparts the fibrous characteristics to this steel enabling it to be threaded or otherwise machined. Thereafter, the steel is permitted to partly or entirely cool, after which it is threaded to provide the interior thread 4 for the reception of a pipe or rod 5 to be connected thereto. v

If it is attempted to thread the neck 3 before treatment in accordance with the present invention, a ragged thread incapable of preventing leakage or of forming a tight joint is provided. After treatment in accordance with the present invention, however, a smooth thread may be easily produced.

The advantages of the present invention arise from the treatment of open-hearth steel, preferably after it has been worked, to

impart Bessemer characteristics enabling it to be machined.

It'will be understood that throughout the specifications and claims I have utilized the terms open-hearth and Bessemer in their generic sense as covering either a steel or the characteristics of such steel which are insteel which may be effectively machined.

herently present therein. Mor particularly, I have used the expression open-hearth characteristics as definitive of a steel which maybe easily worked, and the expression Bessemer characteristics as definitlve of a .1 ai 1. The method" of making artiels'bt manufacture, comprising working a steel having open hearth characteristics, thereafter treating the steel to impart Besscn'ier characteristics, and then machining the steel.

2. The method of metal working, comprising working 0 )en hearth steel to the desired shape, treating at least a portion thereof to provide Bessemer characteristics, and thereafter machining the portion so treated.

3. The method of metal working, comprising locally treating a piece of worked open hearth steel plate to impart Bessemer steel characteristics, and thereafter machining the locally treated portion.

4. The method of metal working, comprising working a piece of open hearth steel plate to shape the same and provide a neck thereon, treating said neck to impart Bessemer steel characteristics thereto and thereby improve its machining characteristics, and thereafter machining the same.

5. The method of metal working, comprising working an open hearth steel plate to shape the same, treating at least a portion of the shaped plate to impart thereto Bessemer steel characteristics, and thereafter threading the treated portion.

6. The method of metal working, com prising adding .to a portion of an open hearth steel plate at least one element ordinarily removed by the open hearth process and retained by the Bessemer process to improve the machining qualities of the metal,

and then machining said portion.

7. The method of metal working, comprising shaping a steel plate low in sulphur and/or phosphorus, thereafter treating at least a portion of said plate to increase the sulphur and/or phosphorous content, and then machining the treated portion.

8. The method of metal working, comprising shaping a steel plate low in sulphur and/or phosphorus, thereafter treating at least a portion of said plate to increase the sulphur and/or phosphorous content, and then threading the treated portion.

9. The method of changing the characteristics of open hearth steel to facilitate'the performance of predetermined machining operations thereon after working, comprising heating the steel, applying thereto a coating containing at least one element substantially removed by the open hearth process, and then machinin the treated steel.

10. The method of Iianging the characteristics of open hearth steel to facilitate the performance of predetermined machining operations thereon after working, comprising heating the steel, applying thereto a coating containing at least one element substantially removed by the'open hearth process, and then threading the treated steel.

11. The method of changing the charac teristi'csofopen hearth steel to' facilitate coating containing the performance of predetermined machining operations thereon after working, comprlsing heating the steel, applying thereto a coating containin sulphur, and then machining the treate steel.

12. The method of changing the characteristics of open hearth steel to facilitate hearth steel plate possessing in certain portions thereof Bessemer steel characteristics.

14. As an article of manufacture, an open hearth steel plate having in at least one portion thereof relatively greater amounts of sulphur and/or phosphorus.

15. As an article of manufacture, a shaped open hearth steel plate havingat least a portion thereof possessing an abnormal percentage of sulphur and/or phosphorus.

16. The method of. making articles of manufacture from steel, which are both my -hand..

worked and machined. comprising taking open hearth steel which is capable of being worked, changing the physical characteristics of the portion to be machined to those of- Bessemer steel and subjecting-the work pieces to both the working and machining processes, substantially as described.

17 The method of maki-n articles of manufacture, comprising pro ucing a steel having open hearth characteristics, working said steel, thereaftertreating the steel to impart Bessemer characteristics, and then machining the steel.

18. The method of forming plates with a threaded boss thereon, comprising forming a plate of open hearth steel, forming a boss thereon by working the metal, coating a face of the boss with a substance which will change the characteristics of the coated portion from that of open hearth to Bessemer steel when heated, heating the coated portion and then threading such coated portion.

In testimony whereof I have hereunto set CHARLES B. GUSHWA. f 

